OBI100 phone LED Off Solution

Finally fixed. Here is the solution for those who might have the same issue in the future:

Actually all come from Verizon router's firewall. Remember Time Warner cable modem to Linksys router. Then OBi100 to the router and house phone line which wired to several rooms. Now Verizon has not cable modem. So the FiOS cable directly to the router thus OBi100 behind the LAN. While OBi100 needs to be in front of the LAN to work. Solution is to put OBi100 in Verizon router's DMZ which bypass the firewall, or in front of the LAN.

First locate OBi100 network configuration. Write down OBi100 static IP address, subnet address (most likely 255.255.255.0) and change gateway IP to Verizon router's IP (most likely 192.168.1.1).

Secondly login Verizon FiOS router configuration- advance menu and on left side choose DMZ enabling. check enable DMZ and put in your OBi100's static IP address. Save.

Reboot router. Reboot OBi100. Your phones at home will work